Foods that are highly salted, pickled, or smoked
Smoking foods such as meat or nuts causes these food items to absorb considerable amounts of the tar that smoke produces. Tar is a known carcinogen. Meats such as bacon, sausage, bologna, and salami are high in fat and salt. Pickled foods are also very high in salts.
There is overwhelming evidence that eating these types of foods greatly increases the risk of colorectal cancer and higher rates of stomach cancer. The rates of stomach cancer are much greater in places such as Japan where a traditional diet contains many foods that are highly salted, and/or smoked.